This invention is probably the best cooler for energy saving devices because it doesn't use energy. It doesn't use electricity, solar photovoltaics, or batteries.
It was invented by a 22 year old British student who has a history of creating innovative, award winning products.
Made from household materials her cooler invention maintains a temperature that preserves perishable foods and medicine.
It is a solar cooler that consists of two tubes with one inside the other. It uses solar heat and evaporation to create natural biological cooling. The principle is similar to how perspiration cools our bodies.
The inner tube is made of metal and is the receptacle used to store perishables. It also keeps the contents dry.
The outer tube is made of any sturdy material such as wood, plastic, bamboo, ceramic or clay and has holes in it.
The inner tube is fitted inside the outer tube with a gap between them which is filled with sand, wool, soil or any material that will absorb water.
Solar energy (sunshine) heats the tube causing the water to evaporate from the gap material. This evaporation removes heat from the inner tube lowering the temperature inside to about 6ºC (42ºF).
Renewing the gap material with water keeps the cooler operating.
When she was 16, Emily Cummins from Keighley, West Yorkshire, won the Young Engineer for Britain Award for a toothpaste container she invented to help people who suffered from arthritis.
The following year she won the Sustainable Design Award for a portable water carrier she invented to help people in developing countries transport water.
A year later, Emily's best cooler invention won the York Merchant Adventurers Award.
"I wanted to keep it really simple and so I set about researching how we cooled things years ago. The simplest method of cooling something could be seen when you look at how we cool biologically - through sweating or evaporation," says Emily.
Emily has traveled to Africa to distribute her invention to those communities most in need of her cooler, where she is known affectionately by residents as "the fridge lady".
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